The synthesis and reactions of thietes (thiacyclobutenes) and thiete S-oxides (e.g. thiete 1,1-dioxide or thiete sulfone) will be investigated. Thietes are sources of thioacroleins which form stable heterocyclic complexes with transition metals (e.g. Fe, Co). The removal of hydrogen (as H., H minus, H plus) from these complexes may yield novel, electronically delocalized species which could function as electron-transfer catalysts. The synthesis of metal-containing tetramers and oligomers involving the thioacrolein ligand will be attempted. The decomposition of thiete sulfone to vinyl sulfene parallels the decomposition of thiete to thioacrolein. Investigation of the cycloaddition of vinyl sulfene to olefins will be continued with a view to the possible uses of this cycloaddition in the synthesis of cycloheptatrienes, bicyclic ketones and hydrocarbons and other structures.